No Spark

My 2002 TJ 4L will suddenly not start. It's not getting any spark. I replaced the Crank Shaft position sensor and ignition coil stip - still no spark?

Anybody have a suggestion of where to go next?

Many thanks!

Fred

Reply to
Fred Garvin
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Reply to
Jerry Bransford

Hmmm. I didn't try the camshart sensor, just the Crank shaft sensor, I think. It's on the bell housing. Where's the camshaft sensor?

No codes.

Reply to
Fred Garvin

It's on the passenger-side where the distributor used to be. The distributor is gone on late model TJ 4.0L engines but the camshaft sensor should still be there being driven off the old distributor shaft IIRC.

Jerry

Fred Garv> Hmmm. I didn't try the camshart sensor, just the Crank shaft sensor, I

Reply to
Jerry Bransford

Fred - do the diagnostic code thing and then tell us what is comes back with. Starting with the ignition off, turn the key on-off-on-off-on in a nice even cadence, then look at the odometer. This is where the Jeep tells you what ails it if it has anything to say. If it has nothing to say it will just say 'done'. If the computer has picked up an error in the system it will show a code or a series of codes. Write them all down and post them here - the folks here will tell you what they mean.

This is easy and free and if it shows codes the answer (or at least a good clue) is handed to you rather than chasing the problem by replacing parts that might or might not be problematic. Do it. Tomes

Reply to
Tomes

Thanks, Tomes. The only thing I received was "Done."

Reply to
Fred Garvin

I'm going after that next. I'll let you know.

Reply to
Fred Garvin

A broken ground wire can cause no spark. The main ground is a mesh strap from the engine head to the firewall and the computer grounds are on a bolt on the passenger side by the oil dipstick.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Fred Garv>

Reply to
Mike Romain

Mike Romain did pass the time by typing:

On the newer I6 the ground strap is a large gauge (2?) stranded copper wire that runs from the coil mounting bolt to the frame. Front passenger side of the engine, hiding behind the alternator. You can see the fat wire and just barely part of the connector in this pic from my 93

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I've had problems with corrosion but not near as much as the old braided lines. That being said, a seperate ground wire between the unused engine mount bolt holes and the frame might be a good idea.

Reply to
DougW

Ah, bummer that it did not help though. It was worth a try and now you know for the future as well. Good luck with this. Tomes

Reply to
Tomes

You nailed it! It was the camshaft sensor. It's running great. Thank you, Jerry. And thanks to all! This is a great group.

Reply to
Fred Garvin

Interesting. The older engines also have a strap from the engine to the frame along with the one from the engine to the firewall.

You must have 'something' grounding the body of the vehicle. At least a cable from the battery negative to the fender.

Moot in this case anyway, the OP had a bad CPS it would seem.

Mike

DougW wrote:

Reply to
Mike Romain

Awesome, a lucky guess. ;)

Jerry

Fred Garv> You nailed it! It was the camshaft sensor. It's running great. Thank you,

Reply to
Jerry Bransford

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L.W.( ßill ) Hughes III

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philthy

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